Trim air filter box top plate to fit accelorator pump...

[Michael Burbidge]

The instructions say to center the FAB top plate on the mounting plate. I can't do that without trimming away some of the top plate to fit around the accelerator pump on the carb.

Did you have to trim the top plate to fit around the accelerator pump?

Thanks,
Michael-

[ArlingtonRV]

Michael,

I didn't build mine, but there is a rather prominent cut out in the mounting plate on the FAB to clear the accelerator pump housing. I recenly made the cut out even larger to facilitate the use of a slightly different K@N filter that allows for installation without cutting a chunk out of the regular filter.

I only have about 2 hours on the new set up, but so far, so good. I learned of the idea from this thread:

http://www.vansairforce.com/communit...arb+air+filter

[crabandy]

Hmmm, do you have any pics? I didn't have to modify the FAB top plate at all for my O-360, you aren't talking about cutting the mounting plate (VA-131-C) are you? Perhaps the O-320 is different?

[ArlingtonRV]

I don't have any pictures. I did it during the last condition inspection and got behind schedule. I had planned to take before and after photos, but forgot until I had it all back together.

I may be talking about something different than you or the OP are talking about. I don't have a part number handy, but I'm talking about the plate that is riveted to the actual FAB that bolts on to the plate mounted to the bottom of the carburetor. I am not talking about the plate mounted to the bottom of the carburetor. Also, I am talking about an RV-4 that was completed in 1997 and things may have changed since then and what I have may not even be what is used now.

[rvbuilder2002]

Originally Posted by Michael Burbidge

Did you have to trim the top plate to fit around the accelerator pump?

Van's sells an Airbox Kit for the carbed O-320 that has a top plate that already contains an opening for the accelerator pump.

Maybe you have the wrong airbox kit?

[Michael Burbidge]

I have the O-320 version. Here's a picture. Note the mounting plate has a cutout for the accelerator pump. What I'm asking about is trimming the top plate to fit around the accelerator pump so that the top plate can be centered on the mounting plate. I'm assuming that's what I need to do.

Thanks,
Michael-

[rvbuilder2002]

Originally Posted by Michael Burbidge

I have the O-320 version. Here's a picture. Note the mounting plate has a cutout for the accelerator pump. What I'm asking about is trimming the top plate to fit around the accelerator pump so that the top plate can be centered on the mounting plate. I'm assuming that's what I need to do.

Thanks,
Michael-

Ahhh.... top plate versus mounting plate...
The mounting plate is the top most, so I confused my self.

Yes you need to slightly trim the top plate, but don't trim the side your pointing to in your photo (the top plate is positioned on the carb backwards).

[Michael Burbidge]

Yes you're right, its backwards. Thanks!

Michael-